Wave-receiver.



PATENTED MAY 31, 1904. B.. W. SHOBMAKER & L. H. GIDDI'NGS.

WAVE RECEIVER. APPLIOATIOI FILED HAY 2, 1902.

I0 HODEL.

vot-w UNITED STATES 7c/asa Patented May 31, 1904.

RICHARD W. SHOEMAKER AND LAWVSEN H. GIDDINGS, OF PASADENA,

' CALIFORNIA.

WAVE-RECEIVER.

SPECIFICATION forming part of Letters Patent No. 761,258, dated my 31, 1904.

Application tiled lay 2, 1902.

To all whom it may concern.-

Be it known that we, RICHARD W. SHOE- MAKER and LAWSEN H. GIDDrNGs, both citizens of the United States, residing at Pasadena, in the county of Los Angeles and State of California, have inventeda new and useful VVave-Receiver, of which the following is a specification.

Our invention relates to an instrument for 1o detecting and receiving electric waves employed in wireless telegraphy, and has for one object to produce an instrument for receiving such waves in which the susceptibility to the waves is continuous and not destroyed after 1 5 receiving each wave.

Another object is to provide a receiver in which the susceptibility to Waves may be as an inherent quality and self-acting and the instrument always in condition to be iniuzo enced by a wave.

Another object is to provide a receiver of the character described which may be adjusted to different degrees of susceptibility.

Another object is to provide a receiver which will be susceptible to Waves of a definite character and not influenced by magnetic influences-such, for instance, as are generated by rotating tbe armature of a dynamo.

Another object is to provide a receiver 3o which does not require more than ordinary care in handling and which is capable of sustaining jars, shocks, and other disturbances and still retain the utmost degree of susceptibility.

A further object is to attain the aforesaid objects by an exceedingly simple device which is self-contained, portable, has but lew parts and no delicate or moving mechanism.

When under the iniuence of a wave, the re- 40 ceiver is in an excited condition, and when the wave subsides the normal condition prevails.f Thus the receiver may have two distinctive conditions, and its tendency is to change from one condition to the other to partake4 of either condition according tothe presence or absence of a wave.

The accompanying drawing illustrates the invention.

1 is a mixture composed of particles of non- Serial No. 105,681. (No model.)

conducting material a and particles of con- SO ducting material b. The mixture is contained in a tube 2, composed of non-conducting material. Plugs 3, composed of a conducting material, confine the mixture under pressure.

The plugs a may be adjustably held in binding-posts 4, as shown. The plugs 3 and mixture 1 form an unbrokencontinuous conductor, the mixture 1 being under such a pressure that the particles of which it is composed are -held from becoming dislodged or shaken .from 6 their positions. The exact pressure is ascertained by. adjusting the plugs until the wavereceiver responds to the coming las well as to the going of a wave. As near as we have ascertained in practice the pressure used, in

' some cases with plugs one-tenth of an inch in diameter, was less than an ounce.

5 is a metallic shield which may inclose the instrument and from which it may be insulated by insulators 6. The shield may act to 7 0 prevent waves from being conducted to the instrument except through the regular chan- The non-conducting particles and the conducting particles `are thoroughly mixed and an even pressure is maintained throughout the mixture. The mixture forms a continuous conductor through which an electric current may be passed and has what may be termed a tendency quality or characteristic which allows it to assume distinctive relative conditions. One condition of the mixture may be such that it forms a relatively low resistance to the flow of 'an electric current,` while another condition of the mixture may be such that it forms a relatively high resistance to the ow of an electric current. The

' mixture is susceptible to electric waves,and

the presence or absence of a wave causes one condition or another to prevail. The prevailing condition of the mixture when not under the inuence of a wave may be termed, for convenience, its normal condition, while the conditionprevailing when the mixture 1s under the iniiuence of a wave may be termed its excitedcondition. When an oscillatory wave is conducted to a mixture, the mixture assumes its excited condition and remains so during the presence of the wave. When the `Wave dies, the mixture naturally assumes its normal condition. r

The device may be arranged and used asa receiver in wireless-telegraph systems in practically the has been used. When the resistance of the mixture is low, the electric current may pass therethrough with -full strength. When an electric wave comes, the resistanceV of the mix ture is raised, and by regulating the electric current to the right degree the resistance; of

the mixture when high may stop the current and divert it into other conductors, 'which maycontain translating devices. Assoon as the wave dies the current may again ilow through the mixture, or the current may be made strong enough to continually flow through the mixture, and a translating device (not shown) of definite resistance may nected in series with this lreceiver, so that when the resistance of the mixture is high the current passing therethrough .will not affect the translating device; lhus when the resistance of the mixture becomes normal the current ilowsat full strength and overcomes the resistance vof the translating device. and causes itto operate, or translating devices may 'be used having a low resistance and when connected in parallel with the wave-receiver will act in a manner the reverse of that which has been just described on account of the current being diverted by the wave-receiver into or through the translating device. i

From the foregoing it will be seen that the receiver is entirely Yautomatic and that the quality, characteristic, or tendency of the mixture to assume the different conditions does not depend upon magnetic 'influence or any mechanical' auxiliary device for its operation. The operation 'of the receiver is n'ot iniluenced by the presence of the electric c urrent.

The susceptibility of the mixture to the waves, or, in other Words, its adjustability,

may be regulated by varyingthe pressure against the'mixture. No definite statement can be made to indicate the exactamount of pressure, as the receiver is adjusted until it works automaticallyi; e., increases in resist- Vance upon the comingof a wave and decreases in resistance upon' the going of a`wave.' stated, we find that when the adjustmentis cer# rect for this automatic action'the pressure is' probably about an ounce. More or less pres' sure may: however, be required 'under other conditions, and conslderablevariation in the pressure' may be made without destroying its susceptibility.

aves of a definite character 'are required to influence the receiver,and the operators may regulate the Apressure on the mixture to suit theiwaves being received.

By experiment We have found that the ex-1 act materials and proportions thereof, which may be in the construction of thereceiver,

same manner in which the coherer4 beconv of conducting material,

`may be varied to a large extent. We have found in practice that the proportion of conducting particles and non-conducting particles may preferably be equal. The non-conducting particles may be relatively fine-for instance, gagng one the conducting particlesmay be-coarser. A

,preferable'ma'terial for the non-conducting particles is powdered glass. A preferable material for the conducting ap rticles is a pow- The alloy may preferably condered allo, tain one-tliird tin and two-thirds silver. A good material for the tube 2 is EIM" The plugs 3 may be of soft iron. The box 5 is not essential; but the use of it allows greater latitude in adj ustability. If the box is employed, it may be connectedto the earth, asshown, by the ground connection nection from the box is a usual practice, although our experiments have not shown any particular advantage resulting therefrom.

7 hundred mesh-while 7. The ground con- 8 and 9 designate conductors affording chanl nels for, the Awaves and the electric current.

1t is evident that many variations in the kind of material used, proportions o the ma- 9o terial, construction, and arrangementof the same may be made without departingfrom the spirit of, ourinvention. i

What we claim,'and desire to secure by Letf ters Patent of the United States, is-

1. A wave-receiver embracing amedium of conducting and non-conducting substances which is directly influenced by the coming and going of a wave, and means for varying the susceptibility ofthe medium.

2'. A wave-receiver embracing a vmedium of conducting and non conducting substances whichis directly influenced by the coming and going of a wave and regulated pressure on the medium.

3. lAn oscillatpry-wave receiver comprising a conductor, a portion of said conductor being IOO means for producing a a mixture of particles of glassand particles said mixture being susceptible to oscillatory waves, the resistance of said mixture being normally low when uninueiiced by said waves andbeing relatively high when influenced by: said waves.

4.' An oscillatory-wave receiver comprising a conductor, a portion of said conductor being IIO a 'mixture of non-conducting particles and I particles of -an alloy of silver and tin, said mixturebeing susceptibletooscillatory waves,

Y5. An oscillatory-wavevreceiver comprising -the resistance of said mixture being normally the conducting particles the non-conducting parti?4 influenced by said waves.

by said waves and being relatively high when 6. A wave-receiver comprising -a tube of non-conducting material, iron plugs in the tube and spaced apart, and a mixture in the space between the plugs consisting of powdered glass an'd a powdered alloy of silver and tin.

7. A wave-receiver comprising a tube of non-conducting material, iron plugs in the tube and spaced apart, and a mixture in the space between the plugs consisting of pow- 

